Lock.



.No. 857,192. PATENTED JUNE 18. .1907

0. P. N IXHOLM.

LOG-K.

APPLICATION FILED FEB. 25, 1907.

ATTORNEYS UNITED STAKES rgrnnr orrron.

CALLE P. NIXHOLM, or MELROSE, MONTANA, ASS'IGNOR or ONE-HALF TO CARL A. NIXHOLM, or BUTTE, MONTANA. I

LOCK.

Specification of Letters Patent.

Patented June 18, 1907.

T at whom it may concern.

Be it known that I, CALLE P. NIXHOLM, a citizen of the United States, residing at Melrose, in the county of Silverbow and State of Montana, have invented a new and useful Look, of which the following is a specification.

This invention relates to looks, and more particularly to that type used on the doors of ouses, the principal object in view being to provide a lock of simple and improved construction, and at the same time sufficiently secure to prevent its being operated by any prdlinary key not made especially for this Other objects and advantages of the invention will be disclosed in the accompanying description and the novel features pointed out in the claims.

In the accompanying. drawing, Figure 1 is a side elevation of the lock with the face plate removed and the bolt in unlocked position. Fig. 2 is a similar view with the bolt in locked position, but showing by dotted lines the key in the act of unlocking the bolt.

Fig. 3 is a vertical cross section on the line 33 of Fig. 2. Fig. 4 is a perspective View of the bolt. Fig. 5 is a similar view of the twin springs. Fig. 6 is a detail view of the bit end of a key for operating the lock.

Similar numerals of reference indicate the same partsin the several figures.

The lock case 1 is of the usual rectangular form with one side permanently closed and the other side with a face plate 2 secured to the case by a screw 3, or other well known means. At one end of the lock is a flange 4 provided with a rectangular or other shaped opening for the head 5 of the-locking bolt 6 to pass through. Beneath the bolt 6, and

forming a rest and guide therefor, is a dia.

phragm 7 occupying the greater portion of the lower half of the lock case in the longitudinal center thereof.

The locking bolt 6 comprises a slender body portion or stem at the outer end of which is the enlarged head 5, while on its inner end are two downwardly extending wings 8 which straddle the upper edgeof the diaphragm 7. Near the wings 8, two lugs 9 also depend from the under surface of bolt 6 one on each side of the diaphragm, the opposing edges of said lugs and wings being inv is thrown and holds it in this position.

clined upwardly and toward each other, as shown in the drawing, to serve as bearing surfaces for the key when the bolt is to be moved. As thus arranged; the locking bolt is securely held and guided in its movement and cannot be thrown out of position however much the lock may be tampered with. A notch 10 is made in one of the upper cor' 'ners of the diaphragm 7 within which the head of the lock bolt is seated when said lock bolt is thrown to unlocked position. The inner end of the lock bolt is cut away at 11 to form a shoulder 12 against which springs 13 are seated when the lock bolt is thrown or moved to locked position. The springs 13, shown in detail in Fig. 5, are made of two flat strips of spring metal placed edge to edge and having a vertical portion 14 and anapproximately horizontal portion 15, the latter portion of each spring being cut away at the proximate edges, as shown, and then curved downwardly and baokwardly on each side of the latch bolt: 6. By thus forming the springs, a shoulder 16 is produced which engages behind the shoulder. 12 when the blphlt e springs are held in place by passing the por tion 14 of each between the end of the lock and a pin 17 projecting. from the back plate of the lock and over a pin 18 secured in the same 'way as the pin 17. The shoulder 16 of the springs 13 rests at all times on the top surface of the lock bolt 6 while the extended cam-shaped fingers 19 cross the lugs 9, wings 8, and the space between them.

Through the back plate of the lock, the diaphragm 7 and'the face plate 2, a keyhole 20 is formed a suitable distance below the inner end of the lock bolt to permit a key to act on the inclined faces of the lugs 9 and wings 8. The key hole is of well known form consisting of an eye for the stem of the key and a narrow opening for the bit. Surrounding the eye on either side of the diaphragm, with the exception of the space reserved for the bit, is a circular ward 21, a similar circular ward 22, but of greater diameter, projects from the inner face 'of the back plate of the lock, and a like ward 23 is formed on the inner side of the face plate. These wards register with openings 24, 25 and 26, respectively, in the key by which the bolt 6 is moved. To prevent the bolt be- 2-7 against which the curved portions 19 of the springs 13 bear and hold the bolt in retracted position.

When a key, similar to* that illustrated in Fig. 6, is placed in the keyhole 20 of a lock constructed as above described, the notches 24', 25 and 26 in the bit of said key register with the wards 21, 22 and 23 of the lock, and the slot 28, which divides said bit into two fingers 29 and 31, will be in. line with the diaphragm 7. Now, by rotating the key in the proper direction to throw the bolt, the fingers 29 and 31 first lift the cam portions 19 of the springs 13, releasing the lateral projections 27 and the bolt 6 from the pressure of the springs. The fingers, then striking the inclined edges of the lugs 9 force the bolt outwardly until a stop 32 of the bolt head 5' strikes the flange 4. This movement of the bolt will carry it sufficiently far to bring the shoulder 12 past the shoulder 16 on the springs 13, which latter immediately drop behind the shoulder 12 and lock the bolt in its projected position. The reverse movement of the key brings the bit thereof against the cam projections 19 of the springs and lifts the shoulder 16 from behind the shoulder 12,

thus enabling the bolt to return within the lock case when the bit engages the inclined edges of the wings 8.

WVhat is claimed is z-- 1. In a look, a case therefor containing a centrally disposed diaphragm, a lock bolt, slidably disposed on one edge of said diaphragm, having an enlarged head provided with a stop at one end, and a broad plate or wing at each side of the opposite end projecting downwardly on each side of said diaphragm.

2. In a lock, a case therefor, a centrally disposed diaphragm in the lower half of the case extending from end to end thereof and having a notch in an upper corner, a lock bolt slidably mounted on the upper edge of said diaphragm having an enlarged head at one end adapted to enter said notch, a broad plate or wing at each side of the opposite end projecting downwardly on the sides of said diaphragm, and a lug on the under side of said lock bolt near each wing, the opposing faces of each lug and wing inclined away from each other from above downwardly.

3. A lock comprising a casing, a centrally disposed diaphragm in the bottom thereof, a locking bolt slidable on one edge of said diaphragm, springs bearing on the top of said locking bolt and having return cam shaped portions, downwardly projecting lugs on said bolt straddling said diaphragm, and lateral projections on said lug seated against the cam shaped portion of said spring.

4. A locking bolt for looks comprising a slender body portion with an enlarged head on one end, a stop on said bolt downwardly projecting wings on the other end forming a guide channel, and downwardly projecting lugs in advance of said wings their opposing edges being inclined upwardly and toward each other, and a lateral projection on each of said lugs.

In testimony that I claim the foregoing as my own, I have hereto affixed my signature in the presence of two witnesses.

CALLE P. N IXI-IOLM.

Witnesses:

F. A. MosELY, RALPH E. DUTCH. 

